GM said it is aware of 31 reported incidents, including 13 front-seat fatalities, involving frontal crashes in which the condition may have caused or contributed to the front airbags not deploying.

In expanding the recall to 1,620,665 vehicles in the United States, Canada and Mexico and a small number overseas, the No. 1 U.S. automaker also said it would review its recall process. It had previously recalled almost 779,000 cars.

“The process employed to examine this phenomenon was not as robust as it should have been,” GM’s North American head, Alan Batey, said in a statement. “We will take an unflinching look at what happened and apply lessons learned here to improve going forward.” GM said it submitted a detailed chronology associated with the initial recall to the U.S. National Highway Traffic Safety Administration on Monday.

All of the crashes occurred off-road and at high speeds, where the probability of serious or fatal injuries was high regardless of airbag deployment, a company spokesman said. Failure to wear seat belts and alcohol use also were factors in some cases, the spokesman said.

The Detroit company previously said the weight on the key ring, road conditions or some other jarring event may cause the ignition switch to move out of the “run” position, turning off the engine and most of the car’s electrical components.

Earlier this month, GM said it was recalling 778,562 Chevrolet Cobalt and Pontiac G5 compact cars from model years 2005 through 2007.

On Tuesday, GM added 842,103 Saturn Ion compact cars from 2003 through 2007 model years, Chevy HHR mid-sized vehicles from 2006 and 2007, and the Pontiac Solstice and Saturn Sky sports cars from 2006 and 2007. GM no longer makes any of the affected cars.

The automaker said it is working with suppliers to increase production of replacement parts and accelerate the process. Batey said GM would work with consumers on a case-by-case basis to minimize inconvenience associated with the recall.

Dealers will replace the ignition switch at no charge, but GM advised that until the fix is made, customers should remove nonessential items from their key rings.

GM said the ignition switch torque performance may not meet company specifications. The involved parts were made in Mexico, according to documents previously filed with the U.S. National Highway Traffic Safety Administration.

Of the new recalled total, 1,367,146 vehicles are in the United States, 235,855 are in Canada, 15,073 are in Mexico and 2,591 were exported outside North America, according to GM.

The power seat and sunroof functions might also be rendered inoperable, according to documents filed with the U.S. National Highway Traffic Safety Administration. A Nissan spokesman said there have been no reports of accidents or injuries related to the issue, but one report of smoke coming from under a dashboard on a truck in Mexico in December.

Dealers will inspect the circuit breaker wire harness and repair for free if needed. The recall is expected to begin in early March, according to the NHTSA documents.